Tampa's Four Green Fields Running Club meets every Tuesday evening at Four Green Fields Irish pub on Platt Street, but participants don't take themselves too seriously. After a noncompetitive 5K down Bayshore Boulevard, runners return to the bar.

Organizer Keith Steiner started the club in March, modelling it after similar groups in Pensacola and Colorado Springs, Colo. An Army soldier who runs regularly, Steiner frequented Four Green Fields and observed that Tuesdays are a slow night for bars. He asked the pub's owners if they'd sponsor a club, supplying a meeting place and free post-race pasta dinner.

"We said, 'Sure, go ahead,' thinking it would last a couple weeks and that would be the end of it," said co-owner Colin Breen. "We make some money on it because they drink afterwards, some of them."

The first event was last March 16 — a Monday, because St. Patrick's Day fell that Tuesday. Sixty-five runners came.

"We pitched it as the first Four Green Fields St. Patrick's Day Run," said Steiner, 36, of South Tampa. "We had people calling here saying, 'What are the prizes?' and all that. People didn't understand that it's not a competition. Even our Web site says we're 'a bunch of drinkers with a running problem.'"

The run starts at roughly 6 p.m. But there's no official clock, no air horn, no numbers pinned to participants.

Through word of mouth, the group has grown to about 200 participants a week. They range from walkers and moms with jogging strollers to hard-core marathoners and Hash House Harriers — members of an international organization that's part-running club, part-pub crawl. Regardless of fitness level, everyone charts the same course along Bayshore at sunset.

"This is a 5K club, and it always will be," Steiner said. "If people want to run a 10K — you can run all the way to MacDill if you want. I'm stopping at the 5K turnaround."

After the workout, most runners gather on the pub's back patio for a free buffet. Many buy beer.

The run is "probably a justification to have a beer on a Tuesday night," Steiner said. "It's more of a social experience than a race." Around holidays, costumes are encouraged.

There have been more than 1,100 unique participants since March, and Steiner expects that number to grow as people tackle their New Year's resolutions.

Elisabeth Cullivan, 32, of Tampa, has participated in more then 15 runs.

"I just come for the exercise. It's not really competitive or anything, so I was happy to join it," said Cullivan, a product manager at Numara Software. "Plus, I get to hang with my dog." About a month ago, Cullivan started bringing her 4-year-old Greyhound, Carl, because it's one of the few 5Ks that allows dogs, she said.

Richard Alley, 36, started jogging a year ago. He linked up with the Four Green Fields group as a way to keep up the fitness he'd achieved when training for the Gasparilla 5K.

"It seemed like almost an insurmountable challenge at the time ... getting ready for that race. I remember mentally struggling through running that 5K," said Alley, of South Tampa. "Since then, things have changed."

Alley, an investment banker, finds the weekly run — followed by a pint or two of Guinness — a great way to unwind from work. As of last week, he'd participated in 38 runs — the most of anyone in the group. On Sunday, Alley will run the full Walt Disney World Marathon.

We'll raise our glasses to that.

Four Green Fields Running Club

The group meets every Tuesday at 6 p.m. at Four Green Fields, 205 Platt St., Tampa. The club meets rain or shine. Arrive by 5:45 p.m. to sign in. Free. All ages. Call (813) 254-4444 or go to fourgreenfields.com/runningclub.htm. Mention the club and get a 10 percent discount at Feet First stores in Tampa and St. Petersburg.